[1985 CCX]

As we all know there were several variants in the process and blue or black engines were produced in these. I know of one that had the exp Ford alloy heads but I am sure there was variety. Remember S/C cars were slow movers so they span a large time period. That is where it gets confusing and details grey.

Guess you have to start with the car you have, very expensive to replicate these cars and hoping you are doing it with a high end car as that is where your money is best spent. In todays world you could punch a 390, new heads, period manifold paint it and get more performance and same visuals than a real anything. My two cents unless you are starting with ERA, HiTech, KMS or CSX spend the cash on the base car as it will be better dollar value as 60's engines ah well they are basic and meant to last versus make power. It reminds me of the guy that say's "I have a Corvette motor in my Monte Carlo" SO WHAT?

If your going to spend the dollars to duplicate originality do it with a car that will at least be worth the effort.
I know of at least one Comp car that used alloy heads and GT40 dry sump.
I know of another that used magnesium intake, ETOH in fuel will eat it up.....
All the best on your quest!